Portable rod or true bender

ABSTRACT

A portable rod bending machine for vise mounted operation with capacity for producing closely spaced mutiple bends in heavy rod stock having a rod clamping section with a fixed jaw, a movable jaw, and a quick acting cam lock. A force application member provides a rotatable bending die to reduce friction against the rod stock. Positional and angle indexing members provide accurate reproduction of bends. Two auxiliary brace members provide additional leverage for the heavy rod stock. A high ratio of bending torque to total weight is achieved by the invention.

United States Patent [191 Becker 4] PORTABLE ROD 0R TRUE BENDER [76]Inventor: Bernhard Becker, 69 W. Saddle River Rd., Saddle River, NJ.07458 [22] Filed: May 25, 1971 [21] Appl. No; 146,727

[52] US. Cl 72/321, 72/32, 72/36 [51] Int. Cl. B2 ld 11 /04, B21c 51/00[58] Field of Search 72/322, 321, 320, 319, 72/293, 216, 217, 218, 32,36

[56} References Cited UNITED STATES PATENTS 940,360 11/1909 Richards72/319 3,521,474 7/1970 Komberec et a1. 72/319 1,206,742 11/1916 Wheeler72/321 1,490,933 4/1924 McCabe 72/321 1,263,301 4/1918 Wheeler 72/321664,943 1/1901 Goldenberg 72/217 960,910 6/1910 Hazen 72/319 704,5217/1902 Dolan et al. 72/310 [451 May 7,1974

FOREIGN PATENTS OR APPLICATIONS 456,646 5/1949 Canada 72/319 PrimaryExaminer-Richard J. Herbst Assistant ExaminerMichael J. Keenan Attorney,Agent, or Firm-Constantine A. Michalos [5 7] ABSTRACT A portable rodbending machine for vise mounted operation with capacity for producingclosely spaced mutiple bends in heavy rod stock having a rod clampingsection with a fixed jaw, a movable jaw, and a quick acting cam lock. Aforce application member provides a rotatable bending die to reducefriction against the rod stock. Positional and angle indexing membersprovide accurate reproduction of bends. Two auxiliary brace membersprovide additional 1everage for the heavy rod stock. A high ratio ofbending torque to total weight is achieved by the invention.

8 Claims, 2 Drawing Figures PORTABLE ROD. OR TRUE BENDER BACKGROUND OFTHE INVENTION 1. Field of the Invention In general, the presentinvention is related to rod bending machines, and in. particular it isconcerned with portable rod bending machines for bending heavy rodstock. i

More particularly, the invention is concerned with a portable rodbending machine with a capacity for producing closely spaced multiplebends in heavy rod which prevented rapid production rates. Another probvlem that existed with'the conventional rod benders was the difficulty ofproducing accurate bends with a predetermined characteristic due to thespringiness of the metal rod and slight structural deformations withinthe rod bender itself.

The present invention overcomes these problem by utilizingrelatively-small but highly leveraged jaws for holding the rod stock inorder to permit closely spaced bends and at the same time minmizing theweight and size of the rod bender for portability; the structure of aquick acting cam lock for gripping the rod stock; the implementation ofpositional and angle indexing devices for accurate bendingcharacteristics; and the structure of the force application member tocounteract the springiness characteristic of the metal rod.

SUMMARY OF THE INVENTION The purpose of the present invention is toprovide a portable rod. bender for vise mounted operation with acapacity for producing closely spaced multiple bends in heavy rod stockand providing accurate bending characteristics therein.

- The operational sequence of rod bending is as follows: the rod benderis securely clamped in'a supporting vise, the positional and angleindexing members are set for the desire bend characteristics, the properbending die is inserted in the die holder, then the'rod stock is clampedbetween the holding jaws of the rod bender by means of a fast acting camlock, and the handle of i the force application member is manuallyturned through the preset angular sector to complete the operation.

Consequently, an object of the invention is to provide a portable rodbender with a capacity for producing closely spaced multiple bends inrelatively heavy bar stock.

Another object of the invention is to provide a rod bender having arelatively small size and weight with respect to its heavy dutyperformance.

Another object of the invention is to provide positional and angleindexing devices for accurate reproduction of bends.

Another object of the invention is to provide a rodv bender whichcounteracts the springiness of metal rods in order to produce accuratebend characteristics.

Another object of the invention is to provide means for rapid clampingof the rod stock in the rod bender for high production rates.

Another object of the invention is to provide auxiliary brace members toincreace bending leverage for relatively heavy rod stock.

Still another object of the invention is to provide structural elementsto prevent distortions in the rod bender and maintain the accuracy ofthe bend characteristics in the rod stock.

Other objects and many additional advantages will be more readilyunderstood by those skilled in the art after a detailed consideration ofthe following specification taken with the accompanying drawings.

8 DESCRIPTION OF THE DRAWING 7 DESCRIPTION OF THE PREFERRED EMBODIMENTReferring to FIGS. 1 and 2 of the drawing the various structuralelements of a rod bending machine 10 are seen mounted ona base section11. Rod stock 12 to be bent into the desired shape, is held in a rodclamping section 13 comprised of a fixed jaw 14, an opposing movable jaw15 and a locking member 16. The locking member 16 itself is comprised ofa frame 17 and a cylindrical cam 18 rotatably mounted on the frame sothat the cam 18 will advance the movable jaw 15 toward the fixed jaw 14and lock the rod stock 12 therebetween when the cam 18 is rotated byexternal means such as a wrench 20 engaging a movable hex projection 19connected to the cam 18.

In order to position the rod stock 12 precisely in the rod bender 10, apositional indexing member 21 is incorporated into the structure of therod bender 10. This positional indexing member 21 is comprised of aguide member 22, mounted to the movable jaw 15, an indexing stop member24 slidably mounted on the guide member 22, and a fastening device 25,such as a bolt, for fastening the indexing stop member 24 at a selectedposition.

The bend angle of the rod stock 12 is preselected by an angle indexingmember 26. This angle indexing member 26 is comprised of a bar stop 27slidably mounted on the frame 17 and a fastening device 28 such as abolt so that the position of the bar stop 27 defines the bend angle ofthe rod stock 12. In order to obtain the required bend contour of therod stock 12 a contour die 29 is bolt mounted to the movable jaw 15.

This contour die 29 is comprised a block of highly tempered steel havingat least one angular edge 31 for bending solid rod stock and at leastone rounded edge 32 for bending hollow rod stock. In operation, theconother than cylindrical and it may be rotatably or fixed in positiondepending upon the material of the rod stock, its size, and the bendingcharacteristics required.

In order to produce accurate bends, in metal rod stock having a springycharacteristic, the rod bender is structured to permit an incrementaldisplacement of the rod stock at the point of force application afterthe prescribed bend angle has been completed, provided the bend angle isless than 90. ln this manner the sprininess characteristic of the rod iscompensated.

For bending heavy rod stock additional leverage is provided by twoauxiliary brace members. A first auxiliary brace member is comprised ofa leverage bar 37 slidably mounted on the fixed jaw member 14 so thatthe point of leverage on the clamped section of the rod stock may beadjusted by means of a fastening device 38 such as a bolt.

A second auxiliary brace member is comprised of an extension bar 44rotatably mounted on the die holder 34 by means ofa fastening device 46such as a bolt. The contacting end 45 of the extension bar is rounded inorder to reduce friction during bending.

A longitudinal projecting member 48, mounted on the bottom surface ofthe base section 11, is utilized for both mounting the rod bendingmachine in a vise and providing additional structural rigidity along itslongitudinal axis.

A transversal mounted structural reenforcement member 50, also mountedon the bottom surface of the base section 11 provides structuralrigidity along the transverse axis of the rod bending machine.

- On important advantage of this rod bending machineis the high bendingtorque to total weight ratio which permits bending heavy rods withoutaffecting the portability feature of the machine. Another advantage ofthe machine is that closely spaced multiple bends in heavy rod stock canbe accomplished by relatively small clamping jaws. Still anotheradvantage of the machine is the high bending accuracy attained byutilizing indexing members, high structural rigidity and compensationfor the springiness characteristic of certain metal rods.

While one embodiment of the invention has been illustrated anddescribed, various changes in the form and relative arrangements of theparts, which will now appear to those skilled in the art may bemadewithout departing from the scope of the invention.

What is claimed is:

1. A portable rod bending machine for vise mounted operation,comprising:

a base section;

a rod clamping section mounted on top surface of said base section, saidrod clamping section having a fixed jaw member, an opposing movable jawmember and a locking member;

a detachable contour die member bolt mounted to said movable jaw member;

a force application member mounted on top surface of said base section;

a positional indexing member connected to said movable jaw member forpositioning a rod stock;

an angle indexing member mounted on said locking member;

a first auxiliary brace member-mounted on said fixed jaw member;

a second auxiliary brace member mounted on said force applicationmember;

a transversely mounted structural reenforcement member on bottom surfaceof said base section to prevent structural distortion thereof; and,

a longitudinally mounted projection member on the bottom surface of saidbase section for mounting said rod bending machine in said vise andthereby providing additional structural rigidity.

2. The structure of claim 1 wherein said locking member comprises:

a frame mounted on top surface of said base section; and, I

a cylindrical cam eccentrically mounted on said frame wherein the axisof rotation of said cam is perpendicular with respect to surface of saidbase section so that said cam will move said movable jaw toward saidfixed jaw and lock the' rod stocking therebetween when said cam isrotated by external means.

3. The structure of claim 1 wherein said force application membercomprised:

a die holder rotatably mounted at one end to said fixed jaw member;

handle means mounted to other end of said die holder; and, i

' a cylindrical bending dierotatably mounted on said die holder so thatfriction between the die and rod stock is substantially reduced.

4. The-structure of claim 1 wherein said indexing member comprises:

a guide member mounted to said movable jaw member;

an indexing stop member slidably mounted on said guide member; and

means for fastening said indexing stop member 'to said guide member at aselected position.

5. The structure of claim 1 wherein saidangle indexing member comprisesa bar stop slidably mounted on said locking member so that position ofbar stop defines the bend angle of the rod stock.-

6. The structure of claim 1 wherein said first auxiliary brace membercomprises a leverage bar slidably mounted on said fixed jaw member sothat point of leverage on clamped section of rod stock may be adjusted.

7. The structure of claim 1 wherein said second auxiliary brace membercomprises an extension bar pivotally mounted on said die holder so thatleverage to the movable section of the rod stock is increased.

8. The structure of claim 1 whereinsaid detachable contour die member iscomprised of a block of tempered steel having at least one angular edgefor bending solid rods and at least one rounded edge for bending hollowrods.

positional

1. A portable rod bending machine for vise mounted operation,comprising: a base section; a rod clamping section mounted on topsurface of said base section, said rod clamping section having a fixedjaw member, an opposing movable jaw member and a locking member; adetachable contour die member bolt mounted to said movable jaw member; aforce application member mounted on top surface of said base section; apositional indexing member connected to said movable jaw member forpositioning a rod stock; an angle indexing member mounted on saidlocking member; a first auxiliary brace member mounted on said fixed jawmember; a second auxiliary brace member mounted on said forceapplication member; a transversely mounted structural reenforcementmember on bottom surface of said base section to prevent structuraldistortion thereof; and, a longitudinally mounted projection member onthe bottom surface of said base section for mounting said rod bendingmachine in said vise and thereby providing additional structuralrigidity.
 2. The structure of claim 1 wherein said locking membercomprises: a frame mounted on top surface of said base section; and, acylindrical cam eccentrically mounted on said frame wherein the axis ofrotation of said cam is perpendicular with respect to surface of saidbase section so that said cam will move said movable jaw toward saidfixed jaw and lock the rod stocking therebetween when said cam isrotated by external means.
 3. The structure of claim 1 wherein saidforce application member comprised: a die holder rotatably mounted atone end to said fixed jaw member; handle means mounted to other end ofsaid die holder; and, a cylindrical bending die rotatably mounted onsaid die holder so that friction between the die and rod stock issubstantially reduced.
 4. The structure of claim 1 wherein saidpositional indexing member comprises: a guide member mounted to saidmovable jaw member; an indexing stop member slidably mounted on saidguide member; and means for fastening said indexing stop member to saidguide member at a selected positioN.
 5. The structure of claim 1 whereinsaid angle indexing member comprises a bar stop slidably mounted on saidlocking member so that position of bar stop defines the bend angle ofthe rod stock.
 6. The structure of claim 1 wherein said first auxiliarybrace member comprises a leverage bar slidably mounted on said fixed jawmember so that point of leverage on clamped section of rod stock may beadjusted.
 7. The structure of claim 1 wherein said second auxiliarybrace member comprises an extension bar pivotally mounted on said dieholder so that leverage to the movable section of the rod stock isincreased.
 8. The structure of claim 1 wherein said detachable contourdie member is comprised of a block of tempered steel having at least oneangular edge for bending solid rods and at least one rounded edge forbending hollow rods.